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Heron Bay property geology map

Regional Geology
The general geology of the property is located within the Schreiber-Marathon green stone belt in the Superior Province of the Canadian Shield. More specifically, the property lies within an Archean metasedimentary - metavolcanic belt trending easterly from the Heron Bay area on Lake Superior. Plutonic rocks constitute a major portion of the map area. The Hemlo gold camp is also located within a portion of the Schreiber- Marathon greenstone belt, and lies approximately 28 km to the east of the property. The general geology of the property is shown on the Heron Bay Sheet, Map 2439, which was mapped by and reported on by T.L. Muir, and associates or the Ontario Department of Mines, 1981. The oldest rocks in the area, with the exception of the pukaskwa Gneissic Complex (Bennett et al, 1969 ) are the felsic, intermediate, and mafic volcanic rocks, two suites of volcanic rocks are present: a tholeitic suite consisting of iron-rich basalt and minor andesite, which lies in the southern part of the regional map area which is termed the Pulpwood-Playter Harbor sequence; and a calc-alkalic suite consisting of dacite to rhyolite pyroclastic breccia, lapilli tuff and crystal tuff as well as lesser andesite and basalt which lies in the northern part of the map area termed the Heron Bay Sequence. Iron formation and thin intercalated tuff and sediment units are present in the tholeiitic rocks to the south (T.L. Muir, 1982, O.G.S Report 218). Siltstone, wacke, and shale units are present within or adjacent to the intermediate to felsic puroclastic rocks of the Heron Bay sequence. Minor andesite and basalt also occurs within this sequence. The property lies within the Heron Bay Sequence. This portion of intermediate pyroclastic rocks and intercalated metasediments is sandwiched between two massive plutons. The Gowan Lake Pluton, which lies to the north, covers the northeastern corner of the property and is a porphyritic biotite-hornblende quartz monzonite. The Heron Bay Pluton, to the south, consists of a porphyritic (plagioclase) biotite-hornblende granodiorite. All of the above mentioned volcanic and sedimentary rock suites are intruded by Late Precambrian felsic dikes and sills, and all previously mentioned rocks except those of the Alkalic complex are intruded by more extensive diabase dikes. A common orientation of the diabase dikes is northerly.